Segments in this Video

Rise of the Vertebrates(04:12)

Human evolution can be traced back to bilateria, which developed in an aquatic environment. Our spinal columns evolved from median dorsal chords around 500 million years ago.

Origins of Sight(06:09)

Humans inherited vertebral columns, skulls, and jaws from fish. Eyes are among the most ancient organs in our bodies. Two scientists have studied primitive marine animals to uncover clues regarding their origin.

Origins of Sight: Part II(04:54)

Sarah Gabbott's research of lamprey eels shows that complex eyeballs existed 300 million years ago. Gavin Young uses digital technology to virtually dissect an ancient ocular globe to better understand the evolution of vision.

Evolution of Appendages (10:14)

Vision helps vertebrates spot predators, locate food, and identify members of their own species. Limbs developed more than 400 million years ago. Zoologist Andrew Gillis believes that gill arches in cartilaginous fishes are evolutionary precursors to limbs.

First Great Sexual Revolution(06:54)

The genetic program that led to the development of human limbs is also related to the evolution of external genitalia. John Long studies the fossils of placoderms to unlock the origins of our sexuality.

Development of Genitals(05:50)

Patrick Tschopp uses chicken embryos to study plasticity, which is important to the formation of genital organs in babies. Researcher Bradley Smith explains the role the cloaca plays in the process.

Improving Human Anatomy(05:08)

Zoologist Guillaume Lecointre describes an aspect of respiration that seems inefficient; he explains hiccups. Long elaborates on the human connection to placoderms.

First Land Dwellers(04:11)

The Bocourt skink could be a distant copy of the first terrestrial tetrapods. Long searches for traces of the first animals to emerge from ancient seas; some may have looked similar to the periophthalmus.

Description

New scientific imaging technologies allow scientists to trace the history of how the human body has developed like never before. The genealogy of our organs shows that we share a long history with other species on the planet. This program examines the first major chapters of our evolution, from the time that our ancestors lived in the oceans. The organs that allow us to see, touch, and reproduce all originate from water.